Identify ischemic area
International guidelines mandate cranial imaging to confirm a 'stroke’ diagnosis. MR or CT imaging of the brain and its supplying vessels identifies the affected brain regions, differentiates types of stroke, and distinguishes stroke from stroke mimicking diseases.
Multimodal MRI provides essential information about ischemic regions, perfusion, hemorrhage, and fluid accumulation in the brain.
MR diffusion-weighted imaging (DWI) is a highly specific and one of the most sensitive techniques available for demonstrating acute infarction.
MR perfusion-weighted imaging (PWI) enables differentiation of viable hypoperfused tissue from a probably nonviable irreversible infarction core. MRI not only offers contrast-enhanced but also contrast- (and injection-) -free Arterial Spin Labeling (ASL) techniques for perfusion evaluation.
In combination, DWI and PWI have proven to be very sensitive in the evaluation of early stroke, particularly when the brainstem or the cerebellum is affected by ischemia.
DWI and PWI sequences diagnostically complement MR angiography (MRA) to indicate vascular occlusions, gradient-recalled echo sequence (GRE) and T2* susceptibility-weighted imaging to exclude intracerebral hemorrhage (ICH), and fluid-attenuated inversion recovery sequence (DarkFluid or FLAIR) to identify abnormal fluid accumulations and subarachnoid hemorrhage.
Siemens workflows and technology help to enable you to perform a complete acute stroke diagnostic protocol within 10 minutes.
Native (non-contrast) CT imaging reliably identifies acute intracranial hemorrhage and most stroke-mimicking diseases. Yet within the first hours after an event not all patients show visible ischemic lesions in plain CT¹.
Individual training and the use of scoring systems can help improve the detection of early signs of infarction in plain CT, but multimodal CT imaging offers early and more reliable evidence for cerebral ischemia.
In clinical practice, plain CT imaging is followed by perfusion CT and CT angiography (CTA). The combination of these three techniques helps exclude stroke mimics and hemorrhage, in identifying the location of ischemia and tissue at risk, and in localizing the site of vascular occlusion or rupture.
With the latest scanning technology and highly efficient workflows, Siemens supports you in completing full multimodal CT imaging within minutes after patient presentation.
1Source: AJNR Am J Neuroradiol. 1996 Oct; 17(9): 1743-8 and PLoS One, 2012 Dec 30; 5(12): e15757